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by gregeric
Sat Mar 17, 2018 8:42 pm
Forum: General discussion
Topic: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE
Replies: 376
Views: 41603

Re: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE

Why does it matter if the PWB has a Wi-Fi antenna but the RF chippery is not fitted? Exactly like the original A and B which seemed to have the same PCB but with different components fitted or left off. Pi 3B+- = Pi 2B+ :P The A had the USB Section of the B removed, entirely different scenario, the...
by gregeric
Sat Mar 17, 2018 7:52 am
Forum: General discussion
Topic: No anti-static bag for 3B+?
Replies: 47
Views: 4424

Re: No anti-static bag for 3B+?

Those KnowCharge anti-static paper bags have been used on Pis coming out of the Embed factory for a good while. As others have reported, my UK made Pi 3B+ came without any apparent ESD protection. It did however arrive sitting on a white card printed with a barcode - I wonder if that has ESD protect...
by gregeric
Fri Mar 16, 2018 8:25 pm
Forum: General discussion
Topic: 3B+ PEN & RUN Header
Replies: 13
Views: 7673

Re: 3B+ PEN & RUN Header

Don't think that wee power LED will account for the 'excess' current. Pure coincidence (?) but 11mA is what i got on the Pi3 with Vcore & 1V8 turned off, 3V3 still up.
by gregeric
Fri Mar 16, 2018 8:02 pm
Forum: General discussion
Topic: 3B+ PEN & RUN Header
Replies: 13
Views: 7673

Re: 3B+ PEN & RUN Header

It stays in that 11 mA state after the PEN-GPIO connection is released, but will boot up again if PEN-GPIO is then reattached Who could've predicted that? I think you might be operating in "undefined behaviour" territory, but don't wish to dissuade you from further experiments. I got the Pi3 down t...
by gregeric
Fri Mar 16, 2018 6:21 pm
Forum: General discussion
Topic: RPi 3B+ Heat/CPU related improvements.
Replies: 50
Views: 8956

Re: RPi 3B+ Heat/CPU related improvements.

See https://en.wikipedia.org/wiki/Flip_chip

On the original 2837, the silicon faced upwards with tiny bond wires to connect to the outside world. Now it's been flipped over and, as per that wiki, bond wires done away with. Instead a more or less direct electrical & thermal connection to the PCB.
by gregeric
Fri Mar 16, 2018 6:06 pm
Forum: General discussion
Topic: 3B+ PEN & RUN Header
Replies: 13
Views: 7673

Re: 3B+ PEN & RUN Header

Wonder why you are seeing 11mA and not less? Also wondering if the thing will spring into life at some point, as the power has been removed from the gate in the SoC which you are using to pull down PEN.
by gregeric
Fri Mar 16, 2018 12:57 pm
Forum: Troubleshooting
Topic: RTC on Stretch
Replies: 5
Views: 920

Re: RTC on Stretch

Is your RTC's backup cell healthy?

Edit: failed to notice that this afflicts 9 raspberries so unlikely to be that.

Checked my DS3231 RTC & with network disconnected it's booting back up with the current time. That's Stretch / kernel 4.9.
by gregeric
Fri Mar 16, 2018 8:14 am
Forum: General discussion
Topic: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE
Replies: 376
Views: 41603

Re: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE

Should've stated, in that test the Pi was in the vertical plane, propped on its long short edge. No case either.

Edit: correct orientation discovered on retrieving Pi3B+ this morning: Pi was stood upright on USB/ethernet sockets.
by gregeric
Fri Mar 16, 2018 6:47 am
Forum: General discussion
Topic: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE
Replies: 376
Views: 41603

Re: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE

Ran a test: no heatsink, all four arm cores churning away overnight. The 2837 flip-chip packaging / PCB heatsink did it's job nicely - no throttling, around 67C, with the task completed in ~12 hours. That same task demands a decent heatsink & ~14 hours on a Pi3. Good job! Dare say it'll need some ex...
by gregeric
Thu Mar 15, 2018 10:15 am
Forum: General discussion
Topic: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE
Replies: 376
Views: 41603

Re: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE

An odd request, but I haven't seen any images of the backside of the Raspberry Pi 3 B+... Probably not notable because it doesn't have the (previously shiniest part of the Pi) wireless chip there anymore. There's such an image on Pimoroni's Pibow 3B+ page: https://shop.pimoroni.com/products/pibow-f...
by gregeric
Thu Mar 15, 2018 8:56 am
Forum: General discussion
Topic: 3B+ PEN & RUN Header
Replies: 13
Views: 7673

Re: 3B+ PEN & RUN Header

The schematic shows PEN by default (nothing connected) is pulled high with 1k8. Pull it low & the PMIC draws < 10uA according to the ds. But you'll need 2-3mA flowing through that pullup to provide a logic low on that pin. So shutdown/standby to the tune of 2-3mA looks possible. It's a safe shutdown...
by gregeric
Thu Mar 15, 2018 6:23 am
Forum: General discussion
Topic: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE
Replies: 376
Views: 41603

Re: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE

What is the maximum current limit available to the USB ports? Looking at the schematic https://www.raspberrypi.org/documentation/hardware/raspberrypi/schematics/rpi-3bplus_reduced_schematic.pdf Grid location A-5 shows U9 (USB power controller) with a part number RT9741 C GV which has a maximum spec...
by gregeric
Wed Mar 14, 2018 2:35 pm
Forum: General discussion
Topic: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE
Replies: 376
Views: 41603

Re: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE

Partial schematics at https://www.raspberrypi.org/documentation/hardware/raspberrypi/schematics/rpi-3bplus_reduced_schematic.pdf show that the enable pin of the new power management IC, MxL7704, is brought out to the RUN header. So true low power standby(<10uA quoted for the PMIC) should be possible...
by gregeric
Wed Mar 14, 2018 2:28 pm
Forum: General discussion
Topic: LAN7515 -- USB bus contention issues?
Replies: 12
Views: 3612

Re: LAN7515 -- USB bus contention issues?

Don't overlook that the onboard enhanced 5MHz WiFi, on a bus orthogonal to USB, will give you ~100Mbps concurrent with USB disk access.
by gregeric
Wed Mar 14, 2018 1:11 pm
Forum: General discussion
Topic: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE
Replies: 376
Views: 41603

Re: New Raspberry Pi model 3B+ 1.4 GHz, 330Mbit Ethernet, 802.11ac, PoE

The http://www.microchip.com/wwwproducts/ProductCompare/LAN7515/LAN9514 page says: # Downstream Ethernet/USB Ports Ethenet x1, USB2.0 x6 Downstream USB Ports 6 but on the top it only says Ethernet Bridge with 4 -port USB 2.0 Hub So what are those 2 extra ports for? Could we possibly have two extra ...
by gregeric
Wed Feb 28, 2018 10:14 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: Device Tree Q&A
Replies: 22
Views: 12267

Re: STICKY: Device Tree Q&A

Great stuff mitchthom - I tried and failed to get capture & playback working with the simple card driver.

I'd recently noticed that the half-stereo to true mono alsa stuff had stopped working since I posted in that thread a year ago. I'll see how your solution compares to my workaround.
by gregeric
Thu Oct 26, 2017 11:33 pm
Forum: Troubleshooting
Topic: Is it really necessary to use WD cable kit for PiDrive 314?
Replies: 5
Views: 1047

Re: Is it really necessary to use WD cable kit for PiDrive 314?

The WD drives are native USB3, backwards compatible with USB2. There's *no* SATA conversion involved (save for hidden in the drive's electronics itself, maybe). Just use whatever USB cable you have to hand - even a micro-USB will poke into one half of that widened connector on the PiDrive314 HDD. Wi...
by gregeric
Fri Jun 02, 2017 2:09 pm
Forum: General discussion
Topic: LEDs already on?
Replies: 4
Views: 719

Re: LEDs already on?

GPIOs 0 through to 8 have weak (~50k) pullups enabled by default at boot - enough to feebly light your grounded LED. Additionally, GPIOs 2&3 have strong (~2k) pullups soldered in place for i2c use on those pins - those pins will light your LED brightly. GPIOs 9-27 have weak pull-downs, so your groun...
by gregeric
Sat May 20, 2017 4:49 pm
Forum: Off topic discussion
Topic: Hospitals no fun, not talking worse.
Replies: 74
Views: 9389

Re: Hospitals no fun, not talking worse.

Hi David. I haven't dug deep, but it appears Google AIY has both a locally synthesised voice, and the more refined online one. Both are female, so may not suit anyways!
by gregeric
Sat May 20, 2017 10:51 am
Forum: Off topic discussion
Topic: Hospitals no fun, not talking worse.
Replies: 74
Views: 9389

Re: Hospitals no fun, not talking worse.

So sorry to hear of your misfortune David and best of luck with recovery. As hippy has suggested, the Google AIY project may be worth looking at. You don't need the Voice HAT to use it - it will work with any playback & capture device. There's a "say" action which repeats whatever comes after "say"....
by gregeric
Fri May 19, 2017 6:55 am
Forum: Beginners
Topic: 3D Printing Question
Replies: 3
Views: 759

Re: 3D Printing Question

You'll need to slice the downloaded 3D object file into printable layers, .stl -> .gcode conversion. At this point you get to dictate the layer thickness, extrusion rate, temperatures, position on bed etc etc parameters to suit your printer. That middle-man can be a laptop running eg Cura for slicin...
by gregeric
Thu May 18, 2017 9:02 pm
Forum: Beginners
Topic: LabView for multiple GPIO output signals
Replies: 1
Views: 458

Re: LabView for multiple GPIO output signals

The complete GPIO bank 0 (BCM0-BCM27) is exposed on the 40 pin header, so in theory you have 28 digital outputs. Note that BCM0 & BCM1 will be pulsed early during the boot process while the VPU firmware looks for an I2C HAT eeprom on those lines (but afaicr it may be possible to disable this in conf...
by gregeric
Wed May 17, 2017 11:29 am
Forum: General discussion
Topic: I found that one resistor was missing next to the HDMI inter
Replies: 6
Views: 1080

Re: I found that one resistor was missing next to the HDMI i

Nah, the CMIO3 works with the CM1. Maybe they use an internal pullup, or it just isn't needed, WJDK.
by gregeric
Wed May 17, 2017 10:20 am
Forum: General discussion
Topic: I found that one resistor was missing next to the HDMI inter
Replies: 6
Views: 1080

Re: I found that one resistor was missing next to the HDMI i

I'd hazard a guess that R14 is the same pullup resistor as R15 on the CMIO boards, on the HDMI_CEC line. There it is a 27K pullup to 3V3 on the CMIO Rev 1.2, but not fitted on the CMIO Rev 3.0.
by gregeric
Tue May 16, 2017 6:58 pm
Forum: AIY Projects
Topic: Play through bluetooth speakers instead.
Replies: 11
Views: 2425

Re: Play through bluetooth speakers instead.

Those changes will not affect any of your mods, and are easily reversible by simply re-enabling the google dtoverlay= and commenting out mine.

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